## test for models containing data-defined bases ## ?makepredictcall ## ?model.frame ## ???? data(sleepstudy,package="lme4") library(splines) ## lm0 <- lm(Reaction~ns(Days,2),sleepstudy) ## attr(terms(lm0),"predvars") ## library(nlme) ## lme1 <- lme(Reaction~ns(Days,2),random=~1|Subject,sleepstudy) ## attr(terms(lme1),"predvars") ## no! ## attr(lme1$terms,"predvars") ## yes ## detach("package:nlme") library(lme4) fm1 <- lmer(Reaction ~ ns(Days,2) + (1|Subject), sleepstudy) fm2 <- lmer(Reaction ~ poly(Days,2) + (1|Subject), sleepstudy) fm3 <- lmer(Reaction ~ poly(Days,2,raw=TRUE) + (1|Subject), sleepstudy) newdat0 <- data.frame(Days = unique(sleepstudy$Days)) newdat <- data.frame(Days = 5:12) tmpf <- function(fit) { with(sleepstudy, { plot (Reaction~Days, xlim=c(0,12)) points(Days, predict(fit), col=2) }) lines(newdat0$ Days, predict(fit,re.form=NA,newdata=newdat0), col=4) lines(newdat $ Days, predict(fit,re.form=NA,newdata=newdat ), col=5) } stopifnot(all.equal(predict(fm2,newdat,re.form=NA), predict(fm3,newdat,re.form=NA))) ## pictures tmpf(fm1) tmpf(fm2) tmpf(fm3) ## test for GLMMs set.seed(101) d <- data.frame(y=rbinom(10,size=1,prob=0.5), x=1:10, f=factor(rep(1:5,each=2))) gm1 <- glmer(y ~ poly(x,2) + (1|f), d, family=binomial) gm2 <- glmer(y ~ poly(x,2,raw=TRUE) + (1|f), d, family=binomial) newdat <- data.frame(x=c(1,4,6)) stopifnot(all.equal(predict(gm1,newdat,re.form=NA), predict(gm2,newdat,re.form=NA),tolerance=3e-6))